Enhanced VegScape for Near-real-time Monitoring of U.S. Vegetation Conditions

VegScape is a web-based operational data service system for U.S. cropland condition monitoring with a suite of geoprocessing and mapping capabilities. This application delivers more than 10 types of vegetation index (VI) products for the Conterminous United States (CONUS) derived from Moderate Resolution Imaging Spectroradiometer (MODIS) data. Since the standard, science-quality Terra/Aqua MODIS products are normally available after 20-48 hours of observation, the MODIS-based VI products on VegScape cannot meet the timeliness requirement for many agricultural applications and decision makings when emergency events, such as storms, floods, wildfires, and droughts, occur. To reduce the latency of MODIS data, NASA has launched the Land, Atmosphere Near-real-time Capability for EOS (LANCE) program to provide Level 0-3 near-real-time (NRT) Terra/Aqua MODIS data within less than 3 hours of observation. To enhance the timeliness of VI products on VegScape, we used LANCE MODIS as the data source to produce a set of NRT VI products including Normalized Difference Vegetation Index (NDVI), Vegetation Condition Index (VCI), Mean-referenced Vegetation Condition Index (MVCI), Ratio to Median Vegetation Condition Index (RMVCI), and Ratio to Previous-year Vegetation Condition Index (RVCI). The use of LANCE MODIS enables the monitoring of U.S. cropland vegetation conditions within 24 hours of observation. Along with the historical VegScape data archive back to 2000, this continuous data set with more than 20 years of vegetation condition observation would be suitable for time series analysis in many research fields such as agriculture, remote sensing, geographical information science and systems, environmental modeling, and Earth system science. The NRT VI data products described in this study as well as the complete volume of VI data archive from 2000-2021 are free to access through the VegScape web portal (https://nassgeodata.gmu.edu/VegScape/).